Factor out cpu core unplug into separate function from
spapr_core_release(). Then use generic hotplug_handler_unplug() to trigger
cpu core unplug, which would call spapr_machine_device_unplug() ->
spapr_core_unplug() in the end.
This way unplug operation is not buried in spapr internals and located
in the same place like in other targets, following similar
logic/call chain across targets.
Acked-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Factor out memory unplug into separate function from spapr_lmb_release().
Then use generic hotplug_handler_unplug() to trigger memory unplug,
which will call spapr_machine_device_unplug() -> spapr_memory_unplug()
in the end.
This way unplug operation is not buried in lmb internals and located in
the same place like in other targets, following similar logic/call chain
across targets.
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We'll be handling unplug of e.g. CPUs and PCDIMMs via the general
hotplug handler soon, so let's add that handler function.
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Let's finish cleaning up the hotplug handler. This check can be
performed in the pre_plug code as the very first thing.
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Let's clean the hotplug handler up by moving lookup of the node into
the function where it is actually being used.
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The node property can always be queried and the value has already been
verified in pc_dimm_realize().
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Remove those unneeded includes to speed up the compilation
process a little bit. (Continue 7eceff5b5a cleanup)
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20180528232719.4721-13-f4bug@amsat.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Rename the 2.13 machines to match the number we're going to
use for the next release.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-id: 20180522104000.9044-5-peter.maydell@linaro.org
Let's make it clear at relevant places that we are dealing with device
memory. That it can be used for memory hotplug is just a special case.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-11-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
[ehabkost: rebased series, solved conflicts at spapr.c]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
We use the machine internally either way, so let's just pass it in then.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-5-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
We can just query it ourselves. When unplugging, we should always be
able to the region (as it was previously plugged). E.g. PPC already
assumed that and used &error_abort.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-4-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Let's allow to query the MemoryHotplugState directly from the machine.
If the pointer is NULL, the machine does not support memory devices. If
the pointer is !NULL, the machine supports memory devices and the
data structure contains information about the applicable physical
guest address space region.
This allows us to generically detect if a certain machine has support
for memory devices, and to generically manage it (find free address
range, plug/unplug a memory region).
We will rename "MemoryHotplugState" to something more meaningful
("DeviceMemory") after we completed factoring out the pc-dimm code into
MemoryDevice code.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-3-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
[ehabkost: rebased series, solved conflicts at spapr.c]
[ehabkost: squashed fix to use g_malloc0()]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
On the qmp level, we already have the concept of memory devices:
"query-memory-devices"
Right now, we only support NVDIMM and PCDIMM.
We want to map other devices later into the address space of the guest.
Such device could e.g. be virtio devices. These devices will have a
guest memory range assigned but won't be exposed via e.g. ACPI. We want
to make them look like memory device, but not glued to pc-dimm.
Especially, it will not always be possible to have TYPE_PC_DIMM as a parent
class (e.g. virtio devices). Let's use an interface instead. As a first
part, convert handling of
- qmp_pc_dimm_device_list
- get_plugged_memory_size
to our new model. plug/unplug stuff etc. will follow later.
A memory device will have to provide the following functions:
- get_addr(): Necessary, as the property "addr" can e.g. not be used for
virtio devices (already defined).
- get_plugged_size(): The amount this device offers to the guest as of
now.
- get_region_size(): Because this can later on be bigger than the
plugged size.
- fill_device_info(): Fill MemoryDeviceInfo, e.g. for qmp.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-2-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
On a POWER9 host, if a guest runs in pre POWER9 compat mode, it necessarily
uses the hash MMU mode. In this case, we shouldn't advertise radix GTSE in
the ibm,arch-vec-5-platform-support DT property as the current code does.
The first reason is that it doesn't make sense, and the second one is that
causes the CAS-negotiated options subsection to be migrated. This breaks
backward migration to QEMU 2.7 and older versions on POWER8 hosts:
qemu-system-ppc64: error while loading state for instance 0x0 of device
'spapr'
qemu-system-ppc64: load of migration failed: No such file or directory
This patch hence initialize CPUs a bit earlier so that we can check the
requested compat mode, and don't set OV5_MMU_RADIX_GTSE for power8 and
older.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
a324d6f166 "spapr: Support ibm,dynamic-memory-v2 property" added
a new feature in the set of CAS-negotiatable options. This causes
the CAS-negotiated options subsection to be migrated, even for old
machine types that don't know about it, and breaks backward migration
to QEMU 2.7 and older versions:
qemu-system-ppc64: error while loading state for instance 0x0 of device
'spapr'
qemu-system-ppc64: load of migration failed: No such file or directory
Since this feature only affects boot time behaviour, it should be
filtered out when we decide to migrate CAS-negotiated options, like
we already do with OV5_FORM1_AFFINITY and OV5_DRCONF_MEMORY.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Under PAPR, only the boot CPU is active when the system starts. Other cpus
must be explicitly activated using an RTAS call. The entry state for the
boot and secondary cpus isn't identical, but it has some things in common.
We're going to add a bit more common setup later, too, so to simplify
make a helper which sets up the common entry state for both boot and
secondary cpu threads.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Current POWER cpus allow for a VRMA, a special mapping which describes a
guest's view of memory when in real mode (MMU off, from the guest's point
of view). Older cpus didn't have that which meant that to support a guest
a special host-contiguous region of memory was needed to give the guest its
Real Mode Area (RMA).
KVM used to provide special calls to allocate a contiguous RMA for those
cases. This was useful in the early days of KVM on Power to allow it to be
tested on PowerPC 970 chips as used in Macintosh G5 machines. Now, those
machines are so old as to be almost irrelevant.
The normal qemu deprecation process would require this to be marked
deprecated then removed in 2 releases. However, this can only be used
with corresponding support in the host kernel - which was dropped
years ago (in c17b98cf "KVM: PPC: Book3S HV: Remove code for PPC970
processors" of 2014-12-03 to be precise). Therefore it should be ok
to drop this immediately.
Just to be clear this only affects *KVM HV* guests with PowerPC 970,
and those already require an ancient host kernel. TCG and KVM PR
guests with PowerPC 970 should still work.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Thomas Huth <thuth@redhat.com>
The new property ibm,dynamic-memory-v2 allows memory to be represented
in a more compact manner in device tree.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Now recent kernels (i.e. since linux-stable commit a346137e9142
("powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes")
support this property to mark initially memory-less NUMA nodes as "possible"
to allow further memory hot-add to them.
Advertise this property for pSeries machines to let guest kernels detect
maximum supported node configuration and benefit from kernel side change
when hot-add memory to specific, possibly empty before, NUMA node.
Signed-off-by: Serhii Popovych <spopovyc@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The env->slb_nr field gives the size of the SLB (Segment Lookaside Buffer).
This is another static-after-initialization parameter of the specific
version of the 64-bit hash MMU in the CPU. So, this patch folds the field
into PPCHash64Options with the other hash MMU options.
This is a bit more complicated that the things previously put in there,
because slb_nr was foolishly included in the migration stream. So we need
some of the usual dance to handle backwards compatible migration.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
The ci_large_pages boolean in CPUPPCState is only relevant to 64-bit hash
MMU machines, indicating whether it's possible to map large (> 4kiB) pages
as cache-inhibitied (i.e. for IO, rather than memory). Fold it as another
flag into the PPCHash64Options structure.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Currently env->mmu_model is a bit of an unholy mess of an enum of distinct
MMU types, with various flag bits as well. This makes which bits of the
field should be compared pretty confusing.
Make a start on cleaning that up by moving two of the flags bits -
POWERPC_MMU_1TSEG and POWERPC_MMU_AMR - which are specific to the 64-bit
hash MMU into a new flags field in PPCHash64Options structure.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
As a rule we prefer to pass PowerPCCPU instead of CPUPPCState, and this
change will make some things simpler later on.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Since commit 7da79a167a, the machine class init function registers
dynamic sysbus device types it supports. Passing an unsupported device
type on the command line causes QEMU to exit with an error message
just after machine init.
It is hence not needed to do the same sanity check at machine reset.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This reverts commit b556854bd8.
Leave change @node type from uint32_t to to int from reverted commit
because node < 0 is always false.
Note that implementing capability or some trick to detect if guest
kernel does not support hot-add to memory: this returns previous
behavour where memory added to first non-empty node.
Signed-off-by: Serhii Popovych <spopovyc@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Both spapr_irq_alloc() and spapr_irq_alloc_block() have an errp
parameter, but they don't use it if XICS hasn't been initialized
yet.
This is doubly wrong:
- all callers do pass a non-null Error **, ie, they expect an error
to be propagated in case of failure
- XICS obviously needs to be initialized before anything starts allocating
IRQs
So this patch turns the check into an assert.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Create a new function serial_max_hds() which returns the number of
serial ports defined by the user. This is needed only by spapr.
This allows us to remove the MAX_SERIAL_PORTS define.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180420145249.32435-14-peter.maydell@linaro.org
Change all the uses of serial_hds[] to go via the new
serial_hd() function. Code change produced with:
find hw -name '*.[ch]' | xargs sed -i -e 's/serial_hds\[\([^]]*\)\]/serial_hd(\1)/g'
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 20180420145249.32435-8-peter.maydell@linaro.org
At the moment the device tree produced by the H_CAS handler has no
reserved map initialized at all which is not correct as at least one
empty record is required to be present as a marker of the end.
This does not cause problems now as the only consumer is SLOF which
does not look at the reserved map area.
However when DTC's "Improve libfdt's memory safety" changeset hits
the QEMU upstream, there will be errors reported and crashes observed.
This fixes the problem by adding an empty entry to the reserved map,
just like create_device_tree() does already.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Make qmp_pc_dimm_device_list() return sorted by start address
list of devices so that it could be reused in places that
would need sorted list*. Reuse existing pc_dimm_built_list()
to get sorted list.
While at it hide recursive callbacks from callers, so that:
qmp_pc_dimm_device_list(qdev_get_machine(), &list);
could be replaced with simpler:
list = qmp_pc_dimm_device_list();
* follow up patch will use it in build_srat()
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au> for ppc part
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
With the new "--nic" command line parameter option, the "old" way of
specifying a NIC model via the nd_table[] is becoming more prominent
again. But for the pseries "spapr-vlan" device, there is a confusing
discrepancy between the model name that is used for "--device" (i.e.
"spapr-vlan") and the model name that has to be used for "--net nic"
or the new "--nic" parameter (i.e. "ibmveth"). Since "spapr-vlan" is
the "real" name of the device, let's allow "spapr-vlan" to be used
as model name for the nd_table[] entries, too.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This adds a possibility for the platform to tell VFIO not to emulate MSIX
so MMIO memory regions do not get split into chunks in flatview and
the entire page can be registered as a KVM memory slot and make direct
MMIO access possible for the guest.
This enables the entire MSIX BAR mapping to the guest for the pseries
platform in order to achieve the maximum MMIO preformance for certain
devices.
Tested on:
LSI Logic / Symbios Logic SAS3008 PCI-Express Fusion-MPT SAS-3 (rev 02)
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Linux kernel commit 2a9d832cc9aae21ea827520fef635b6c49a06c6d
(of: Add bindings for chosen node, stdout-path) deprecated chosen property
"linux,stdout-path" and "stdout".
Introduce the new property "stdout-path" and continue supporting the older
property to remain compatible with existing/older firmware. This older property
can be deprecated after 5 years.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The sxxm (speculative execution exploit mitigation) machine type is a
variant of the 2.12 machine type with workarounds for speculative
execution vulnerabilities enabled by default.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
VSMT must be set in order to compute VCPU ids. This means that the
following functions must not be called before spapr_set_vsmt_mode()
was called:
- spapr_vcpu_id()
- spapr_is_thread0_in_vcore()
- xics_max_server_number()
We had a recent regression where the latter would be called before VSMT
was set, and broke migration of some old machine types. This patch
adds assert() in the above functions to avoid problems in the future.
Also, since VSMT is really a CPU related thing, spapr_set_vsmt_mode() is
now called from spapr_init_cpus(), just before the first VSMT user.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Some older machine types create more ICPs than needed. We hence
need to register up to xics_max_server_number() dummy ICPs to
accomodate the migration of these machine types.
Recent VSMT rework changed xics_max_server_number() to return
DIV_ROUND_UP(max_cpus * spapr->vsmt, smp_threads)
instead of
DIV_ROUND_UP(max_cpus * kvmppc_smt_threads(), smp_threads);
The change is okay but it requires spapr->vsmt to be set, which
isn't the case with the current code. This causes the formula to
return zero and we don't create dummy ICPs. This breaks migration
of older guests as reported here:
https://bugzilla.redhat.com/show_bug.cgi?id=1549087
The dummy ICP workaround doesn't really have a dependency on XICS
itself. But it does depend on proper VCPU id numbering and it must
be applied before creating vCPUs (ie, creating real ICPs). So this
patch moves the workaround to spapr_init_cpus(), which already
assumes VSMT to be set.
Fixes: 72194664c8 ("spapr: use spapr->vsmt to compute VCPU ids")
Reported-by: Lukas Doktor <ldoktor@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit 5d0fb1508e "spapr: consolidate the VCPU id numbering logic
in a single place" introduced a helper to detect thread0 of a virtual
core based on its VCPU id. This is used to create CPU core nodes in
the DT, but it is broken in TCG.
$ qemu-system-ppc64 -nographic -accel tcg -machine dumpdtb=dtb.bin \
-smp cores=16,maxcpus=16,threads=1
$ dtc -f -O dts dtb.bin | grep POWER8
PowerPC,POWER8@0 {
PowerPC,POWER8@8 {
instead of the expected 16 cores that we get with KVM:
$ dtc -f -O dts dtb.bin | grep POWER8
PowerPC,POWER8@0 {
PowerPC,POWER8@8 {
PowerPC,POWER8@10 {
PowerPC,POWER8@18 {
PowerPC,POWER8@20 {
PowerPC,POWER8@28 {
PowerPC,POWER8@30 {
PowerPC,POWER8@38 {
PowerPC,POWER8@40 {
PowerPC,POWER8@48 {
PowerPC,POWER8@50 {
PowerPC,POWER8@58 {
PowerPC,POWER8@60 {
PowerPC,POWER8@68 {
PowerPC,POWER8@70 {
PowerPC,POWER8@78 {
This happens because spapr_get_vcpu_id() maps VCPU ids to
cs->cpu_index in TCG mode. This confuses the code in
spapr_is_thread0_in_vcore(), since it assumes thread0 VCPU
ids to have a spapr->vsmt spacing.
spapr_get_vcpu_id(cpu) % spapr->vsmt == 0
Actually, there's no real reason to expose cs->cpu_index instead
of the VCPU id, since we also generate it with TCG. Also we already
set it explicitly in spapr_set_vcpu_id(), so there's no real reason
either to call kvm_arch_vcpu_id() with KVM.
This patch unifies spapr_get_vcpu_id() to always return the computed
VCPU id both in TCG and KVM. This is one step forward towards KVM<->TCG
migration.
Fixes: 5d0fb1508e
Reported-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Several places in the code need to calculate a VCPU id:
(cpu_index / smp_threads) * spapr->vsmt + cpu_index % smp_threads
(core_id / smp_threads) * spapr->vsmt (1 user)
index * spapr->vsmt (2 users)
or guess that the VCPU id of a given VCPU is the first thread of a virtual
core:
index % spapr->vsmt != 0
Even if the numbering logic isn't that complex, it is rather fragile to
have these assumptions open-coded in several places. FWIW this was
proved with recent issues related to VSMT.
This patch moves the VCPU id formula to a single function to be called
everywhere the code needs to compute one. It also adds an helper to
guess if a VCPU is the first thread of a VCORE.
Signed-off-by: Greg Kurz <groug@kaod.org>
[dwg: Rename spapr_is_vcore() to spapr_is_thread0_in_vcore() for clarity]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The spapr_vcpu_id() function is an accessor actually. Let's rename it
for symmetry with the recently added spapr_set_vcpu_id() helper.
The motivation behind this is that a later patch will consolidate
the VCPU id formula in a function and spapr_vcpu_id looks like an
appropriate name.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The VCPU ids are currently computed and assigned to each individual
CPU threads in spapr_cpu_core_realize(). But the numbering logic
of VCPU ids is actually a machine-level concept, and many places
in hw/ppc/spapr.c also have to compute VCPU ids out of CPU indexes.
The current formula used in spapr_cpu_core_realize() is:
vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i
where:
cc->core_id is a multiple of smp_threads
cpu_index = cc->core_id + i
0 <= i < smp_threads
So we have:
cpu_index % smp_threads == i
cc->core_id / smp_threads == cpu_index / smp_threads
hence:
vcpu_id =
(cpu_index / smp_threads) * spapr->vsmt + cpu_index % smp_threads;
This formula was used before VSMT at the time VCPU ids where computed
at the target emulation level. It has the advantage of being useable
to derive a VPCU id out of a CPU index only. It is fitted for all the
places where the machine code has to compute a VCPU id.
This patch introduces an accessor to set the VCPU id in a PowerPCCPU object
using the above formula. It is a first step to consolidate all the VCPU id
logic in a single place.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Since the introduction of VSMT in 2.11, the spacing of VCPU ids
between cores is controllable through a machine property instead
of being only dictated by the SMT mode of the host:
cpu->vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i
Until recently, the machine code would try to change the SMT mode
of the host to be equal to VSMT or exit. This allowed the rest of
the code to assume that kvmppc_smt_threads() == spapr->vsmt is
always true.
Recent commit "8904e5a75005 spapr: Adjust default VSMT value for
better migration compatibility" relaxed the rule. If the VSMT
mode cannot be set in KVM for some reasons, but the requested
CPU topology is compatible with the current SMT mode, then we
let the guest run with kvmppc_smt_threads() != spapr->vsmt.
This breaks quite a few places in the code, in particular when
calculating DRC indexes.
This is what happens on a POWER host with subcores-per-core=2 (ie,
supports up to SMT4) when passing the following topology:
-smp threads=4,maxcpus=16 \
-device host-spapr-cpu-core,core-id=4,id=core1 \
-device host-spapr-cpu-core,core-id=8,id=core2
qemu-system-ppc64: warning: Failed to set KVM's VSMT mode to 8 (errno -22)
This is expected since KVM is limited to SMT4, but the guest is started
anyway because this topology can run on SMT4 even with a VSMT8 spacing.
But when we look at the DT, things get nastier:
cpus {
...
ibm,drc-indexes = <0x4 0x10000000 0x10000004 0x10000008 0x1000000c>;
This means that we have the following association:
CPU core device | DRC | VCPU id
-----------------+------------+---------
boot core | 0x10000000 | 0
core1 | 0x10000004 | 4
core2 | 0x10000008 | 8
core3 | 0x1000000c | 12
But since the spacing of VCPU ids is 8, the DRC for core1 points to a
VCPU that doesn't exist, the DRC for core2 points to the first VCPU of
core1 and and so on...
...
PowerPC,POWER8@0 {
...
ibm,my-drc-index = <0x10000000>;
...
};
PowerPC,POWER8@8 {
...
ibm,my-drc-index = <0x10000008>;
...
};
PowerPC,POWER8@10 {
...
No ibm,my-drc-index property for this core since 0x10000010 doesn't
exist in ibm,drc-indexes above.
...
};
};
...
interrupt-controller {
...
ibm,interrupt-server-ranges = <0x0 0x10>;
With a spacing of 8, the highest VCPU id for the given topology should be:
16 * 8 / 4 = 32 and not 16
...
linux,phandle = <0x7e7323b8>;
interrupt-controller;
};
And CPU hot-plug/unplug is broken:
(qemu) device_del core1
pseries-hotplug-cpu: Cannot find CPU (drc index 10000004) to remove
(qemu) device_del core2
cpu 4 (hwid 8) Ready to die...
cpu 5 (hwid 9) Ready to die...
cpu 6 (hwid 10) Ready to die...
cpu 7 (hwid 11) Ready to die...
These are the VCPU ids of core1 actually
(qemu) device_add host-spapr-cpu-core,core-id=12,id=core3
(qemu) device_del core3
pseries-hotplug-cpu: Cannot find CPU (drc index 1000000c) to remove
This patches all the code in hw/ppc/spapr.c to assume the VSMT
spacing when manipulating VCPU ids.
Fixes: 8904e5a750
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We ignore silently the value of smp_threads when we set
the default VSMT value, and if smp_threads is greater than VSMT
kernel is going into trouble later.
Fixes: 8904e5a750
("spapr: Adjust default VSMT value for better migration compatibility")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit bcb5ce08cf ("spapr: Rename machine init functions for clarity")
renamed ppc_spapr_reset to spapr_machine_reset and ppc_spapr_init
to spapr_machine_init. Let's also rename the references in
comments.
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Add new tristate cap cap-ibs to represent the indirect branch
serialisation capability.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Add new tristate cap cap-sbbc to represent the speculation barrier
bounds checking capability.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
